scholarly journals Characterization of Temporal Protein Production in Pseudomonas aeruginosa Biofilms

2005 ◽  
Vol 187 (23) ◽  
pp. 8114-8126 ◽  
Author(s):  
Christopher J. Southey-Pillig ◽  
David G. Davies ◽  
Karin Sauer
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance ◽  
Biofilm Formation ◽  
Protein Production ◽  
Developmental Stages ◽  
Developmental Process ◽  
Developmental Cycle ◽  
Specific Proteins ◽  
Biofilm Development ◽  
The Impact

ABSTRACT Phenotypic and genetic evidence supporting the notion of biofilm formation as a developmental process is growing. In the present work, we provide additional support for this hypothesis by identifying the onset of accumulation of biofilm-stage specific proteins during Pseudomonas aeruginosa biofilm maturation and by tracking the abundance of these proteins in planktonic and three biofilm developmental stages. The onset of protein production was found to correlate with the progression of biofilms in developmental stages. Protein identification revealed that proteins with similar function grouped within similar protein abundance patterns. Metabolic and housekeeping proteins were found to group within a pattern separate from virulence, antibiotic resistance, and quorum-sensing-related proteins. The latter were produced in a progressive manner, indicating that attendant features that are characteristic of biofilms such as antibiotic resistance and virulence may be part of the biofilm developmental process. Mutations in genes for selected proteins from several protein production patterns were made, and the impact of these mutations on biofilm development was evaluated. The proteins cytochrome c oxidase, a probable chemotaxis transducer, a two-component response regulator, and MexH were produced only in mature and late-stage biofilms. Mutations in the genes encoding these proteins did not confer defects in growth, initial attachment, early biofilm formation, or twitching motility but were observed to arrest biofilm development at the stage of cell cluster formation we call the maturation-1 stage. The results indicated that expression of theses genes was required for the progression of biofilms into three-dimensional structures on abiotic surfaces and the completion of the biofilm developmental cycle. Reverse transcription-PCR analysis confirmed the detectable change in expression of the respective genes ccoO, PA4101, and PA4208. We propose a possible mechanism for the role of these biofilm-specific proteins in biofilm formation.

scholarly journals Antimicrobial Resistance and Biofilm Formation of Pseudomonas aeruginosa

10.3823/846 ◽  
2020 ◽  
Vol 10 (2) ◽  
Author(s):  
Abdelraouf A Elmanama ◽  
Suhaila Al-Sheboul ◽  
Renad I Abu-Dan
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance ◽  
Antimicrobial Resistance ◽  
Quorum Sensing ◽  
Bacterial Adhesion ◽  
Biofilm Formation ◽  
Bacterial Infections ◽  
Developmental Stages ◽  
Infection Site ◽  
Major Virulence Factor

Abstract Pseudomonas aeruginosa threatens patient’s care. It is considered as the most complicated health care associated pathogen to be eliminated from infection site. The biofilm forming ability of P. aeruginosa, being a major virulence factor for most pathogenic microorganism, protects it from host immunity and contribute to antibiotic resistance of this organism. It is estimated that about 80% of infectious diseases are due to biofilm mode of growth. Biofilm forming ability of bacteria imparts antimicrobial resistance that leads to many persistent and chronic bacterial infections. The world is becoming increasingly under the threat of entering the “post-antibiotic era”, an era in which the rate of death from bacterial infections is higher than from cancer. This review focus on P. aeruginosa biofilm forming ability; definition, developmental stages, and significance. In addition, the quorum sensing and the antibiotic resistance of this pathogen is discussed. Keywords: Biofilm; bacterial adhesion; Pseudomonas aeruginosa; antimicrobial resistance; quorum sensing.

scholarly journals Phenotypic Characterization of Streptococcus pneumoniae Biofilm Development

2006 ◽  
Vol 188 (7) ◽  
pp. 2325-2335 ◽  
Author(s):  
Magee Allegrucci ◽  
F. Z. Hu ◽  
K. Shen ◽  
J. Hayes ◽  
Garth D. Ehrlich ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Biofilm Formation ◽  
Protein Identification ◽  
Development Process ◽  
Developmental Stages ◽  
Developmental Process ◽  
Phenotypic Characterization ◽  
Biofilm Growth ◽  
Cell Counts ◽  
Biofilm Development

ABSTRACT Streptococcus pneumoniae is among the most common pathogens associated with chronic otitis media with effusion, which has been hypothesized to be a biofilm disease. S. pneumoniae has been shown to form biofilms, however, little is known about the developmental process, the architecture, and the changes that occur upon biofilm development. In the current study we made use of a continuous-culture biofilm system to characterize biofilm development of 14 different S. pneumoniae strains representing at least 10 unique serotypes. The biofilm development process was found to occur in three distinct stages, including initial attachment, cluster formation, and biofilm maturation. While all 14 pneumococcal strains displayed similar developmental stages, the mature biofilm architecture differed significantly among the serotypes tested. Overall, three biofilm architectural groups were detected based on biomass, biofilm thickness, and cluster size. The biofilm viable cell counts and total protein concentration increased steadily over the course of biofilm development, reaching ∼8 × 108 cells and ∼15 mg of protein per biofilm after 9 days of biofilm growth. Proteomic analysis confirmed the presence of distinct biofilm developmental stages by the detection of multiple phenotypes over the course of biofilm development. The biofilm development process was found to correlate not only with differential production of proteins but also with a dramatic increase in the number of detectable proteins, indicating that biofilm formation by S. pneumoniae may be a far more complex process than previously anticipated. Protein identification revealed that proteins involved in virulence, adhesion, and resistance were more abundant under biofilm growth conditions. A possible role of the identified proteins in biofilm formation is discussed.

Confocal and SEM imaging to demonstrate food pathogen- biofilm biocontrol by pyocyanin from Pseudomonas aeruginosa BTRY1

2016 ◽  
Vol 6 (01) ◽  
pp. 5218
Author(s):  
Laxmi Mohandas ◽  
Anju T. R. ◽  
Sarita G. Bhat*
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Antibiofilm Activity ◽  
Opportunistic Pathogens ◽  
Redox Active ◽  
Sem Imaging ◽  
The Impact

An assortment of redox-active phenazine compounds like pyocyanin with their characteristic blue-green colour are synthesized by Pseudomonas aeruginosa, Gram-negative opportunistic pathogens, which are also considered one of the most commercially valuable microorganisms. In this study, pyocyanin from Pseudomonas aeruginosa BTRY1 from food sample was assessed for its antibiofilm activity by micro titer plate assay against strong biofilm producers belonging to the genera Bacillus, Staphylococcus, Brevibacterium and Micrococcus. Pyocyanin inhibited biofilm activity in very minute concentrations. This was also confirmed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). Both SEM and CLSM helped to visualize the biocontrol of biofilm formation by eight pathogens. The imaging and quantification by CLSM also established the impact of pyocyanin on biofilm-biocontrol mainly in the food industry.

scholarly journals Sodium Salicylate Influences the Pseudomonas aeruginosa Biofilm Structure and Susceptibility Towards Silver

2021 ◽  
Vol 22 (3) ◽  
pp. 1060
Author(s):  
Erik Gerner ◽  
Sofia Almqvist ◽  
Peter Thomsen ◽  
Maria Werthén ◽  
Margarita Trobos
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Sodium Salicylate ◽  
Treatment Strategies ◽  
Cell Aggregation ◽  
Wound Fluid ◽  
Global Challenge ◽  
3D Collagen ◽  
Biofilm Development ◽  
Biofilm Structure

Hard-to-heal wounds are typically infected with biofilm-producing microorganisms, such as Pseudomonas aeruginosa, which strongly contribute to delayed healing. Due to the global challenge of antimicrobial resistance, alternative treatment strategies are needed. Here, we investigated whether inhibition of quorum sensing (QS) by sodium salicylate in different P. aeruginosa strains (QS-competent, QS-mutant, and chronic wound strains) influences biofilm formation and tolerance to silver. Biofilm formation was evaluated in simulated serum-containing wound fluid in the presence or absence of sodium salicylate (NaSa). Biofilms were established using a 3D collagen-based biofilm model, collagen coated glass, and the Calgary biofilm device. Furthermore, the susceptibility of 48-h-old biofilms formed by laboratory and clinical strains in the presence or absence of NaSa towards silver was evaluated by assessing cell viability. Biofilms formed in the presence of NaSa were more susceptible to silver and contained reduced levels of virulence factors associated with biofilm development than those formed in the absence of NaSa. Biofilm aggregates formed by the wild-type but not the QS mutant strain, were smaller and less heterogenous in size when grown in cultures with NaSa compared to control. These data suggest that NaSa, via a reduction of cell aggregation in biofilms, allows the antiseptic to become more readily available to cells.

scholarly journals Draft Genome Sequence of a Clinically Isolated Extensively Drug-Resistant Pseudomonas aeruginosa Strain

2016 ◽  
Vol 4 (2) ◽  
Author(s):  
Bhavani Manivannan ◽  
Niranjana Mahalingam ◽  
Sudhir Jadhao ◽  
Amrita Mishra ◽  
Pravin Nilawe ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance ◽  
Genome Assembly ◽  
Biofilm Formation ◽  
Draft Genome ◽  
Drug Resistant ◽  
Draft Genome Assembly ◽  
Extensively Drug Resistant ◽  
History Of ◽  
Urinary Tuberculosis

We present the draft genome assembly of an extensively drug-resistant (XDR) Pseudomonas aeruginosa strain isolated from a patient with a history of genito urinary tuberculosis. The draft genome is 7,022,546 bp with a G+C content of 65.48%. It carries 7 phage genomes, genes for quorum sensing, biofilm formation, virulence, and antibiotic resistance.

scholarly journals Lon Protease Has Multifaceted Biological Functions inAcinetobacter baumannii

2018 ◽  
Vol 201 (2) ◽  
Author(s):  
Carly Ching ◽  
Brendan Yang ◽  
Chineme Onwubueke ◽  
David Lazinski ◽  
Andrew Camilli ◽  
...  
Keyword(s):  
Acinetobacter Baumannii ◽  
Biofilm Formation ◽  
Developmental Process ◽  
Cell Envelope ◽  
Opportunistic Pathogen ◽  
Lon Protease ◽  
Content Type ◽  
Hospital Acquired Infections ◽  
Biofilm Development ◽  
Hospital Acquired

ABSTRACTAcinetobacter baumanniiis a Gram-negative opportunistic pathogen that is known to survive harsh environmental conditions and is a leading cause of hospital-acquired infections. Specifically, multicellular communities (known as biofilms) ofA. baumanniican withstand desiccation and survive on hospital surfaces and equipment. Biofilms are bacteria embedded in a self-produced extracellular matrix composed of proteins, sugars, and/or DNA. Bacteria in a biofilm are protected from environmental stresses, including antibiotics, which provides the bacteria with selective advantage for survival. Although some gene products are known to play roles in this developmental process inA. baumannii, mechanisms and signaling remain mostly unknown. Here, we find that Lon protease inA. baumanniiaffects biofilm development and has other important physiological roles, including motility and the cell envelope. Lon proteases are found in all domains of life, participating in regulatory processes and maintaining cellular homeostasis. These data reveal the importance of Lon protease in influencing keyA. baumanniiprocesses to survive stress and to maintain viability.IMPORTANCEAcinetobacter baumanniiis an opportunistic pathogen and is a leading cause of hospital-acquired infections.A. baumanniiis difficult to eradicate and to manage, because this bacterium is known to robustly survive desiccation and to quickly gain antibiotic resistance. We sought to investigate biofilm formation inA. baumannii, since much remains unknown about biofilm formation in this bacterium. Biofilms, which are multicellular communities of bacteria, are surface attached and difficult to eliminate from hospital equipment and implanted devices. Our research identifies multifaceted physiological roles for the conserved bacterial protease Lon inA. baumannii. These roles include biofilm formation, motility, and viability. This work broadly affects and expands understanding of the biology ofA. baumannii, which will permit us to find effective ways to eliminate the bacterium.

scholarly journals Relationship between type III secretion toxins, biofilm formation, and antibiotic resistance in clinical Pseudomonas aeruginosa isolates

2021 ◽  
Vol 11 (6) ◽  
pp. 1075-1082
Author(s):  
S. Derakhshan ◽  
A. Rezaee ◽  
Sh. Mohammadi
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Antibiotic Resistance ◽  
Multidrug Resistance ◽  
Type Iii Secretion ◽  
Biofilm Formation ◽  
Virulence Gene ◽  
Microtiter Plate ◽  
P Value ◽  
Type Iii ◽  
Disk Diffusion Assay

Background and aim. Pseudomonas aeruginosa is considered as a notorious pathogen due to its multidrug resistance and life threatening infections. We investigated the relationship between type III secretion toxins, biofilm formation, and antibiotic resistance among clinical P. aeruginosa isolates. Methods. A total of 70 genetically distinct clinical P. aeruginosa isolates were characterized for antibiotic resistance by disk diffusion assay. Biofilm formation was evaluated by microtiter plate method and presence of four exo genes (exoS, exoU, exoT and exoY) was investigated by PCR. A p-value < 0.05 was regarded statistically significant. Results. The most effective antibiotics were Meropenem and Piperacillin. Multidrug resistance was more prevalent in the ciprofloxacin-resistant isolates than in the susceptible isolates. The most frequently identified exo was exoS (37.1%). Genotype exoS/exoT was found in 4 isolates, while genotype exoU/exoT was not found. Prevalence of exoS was generally higher in the susceptible isolates than in the resistant isolates. A significant association was found between the formation of strong biofilm and resistance to antibiotics (p < 0.05). Prevalence of exoY and exoU was higher in the non-strong biofilm producers compared to the strong biofilm producers. Conclusion. Our study revealed formation of strong biofilm along with antibiotic resistance and the presence of exo genes in P. aeruginosa isolates. Knowledge of virulence gene profiles and biofilm formation may be useful in deciding appropriate treatment.

scholarly journals PmtA Regulates Pyocyanin Expression and Biofilm Formation in Pseudomonas aeruginosa

2021 ◽  
Vol 12 ◽  
Author(s):  
Amy V. Thees ◽  
Kathryn M. Pietrosimone ◽  
Clare K. Melchiorre ◽  
Jeremiah N. Marden ◽  
Joerg Graf ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pseudomonas Aeruginosa ◽  
Metal Binding ◽  
Biofilm Formation ◽  
Binding Capacity ◽  
Opportunistic Pathogen ◽  
Small Molecular Weight ◽  
Heavy Metal Binding ◽  
The Impact

The opportunistic pathogen Pseudomonas aeruginosa expresses a small molecular weight, cysteine-rich protein (PmtA), identified as a metallothionein (MT) protein family member. The MT family proteins have been well-characterized in eukaryotes as essential for zinc and copper homeostasis, protection against oxidative stress, and the ability to modify a variety of immune activities. Bacterial MTs share sequence homology, antioxidant chemistry, and heavy metal-binding capacity with eukaryotic MTs, however, the impact of bacterial MTs on virulence and infection have not been well-studied. In the present study, we investigated the role of PmtA in P. aeruginosa PAO1 using a PmtA-deficient strain (ΔpmtA). Here we demonstrated the virulence factor, pyocyanin, relies on the expression of PmtA. We showed that PmtA may be protective against oxidative stress, as an alternative antioxidant, glutathione, can rescue pyocyanin expression. Furthermore, the expression of phzM, which encodes a pyocyanin precursor enzyme, was decreased in the ΔpmtA mutant during early stationary phase. Upregulated pmtA expression was previously detected in confluent biofilms, which are essential for chronic infection, and we observed that the ΔpmtA mutant was disrupted for biofilm formation. As biofilms also modulate antibiotic susceptibility, we examined the ΔpmtA mutant susceptibility to antibiotics and found that the ΔpmtA mutant is more susceptible to cefepime and ciprofloxacin than the wild-type strain. Finally, we observed that the deletion of pmtA results in decreased virulence in a waxworm model. Taken together, our results support the conclusion that PmtA is necessary for the full virulence of P. aeruginosa and may represent a potential target for therapeutic intervention.

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